1. Technical Field
This invention relates generally to optical devices, and more particularly to optical redirection devices suitable for distortion correction use in infinite focus projection systems.
2. Background Art
Scanned laser projection devices facilitate the production of brilliant images created with vibrant colors. Scanned systems, such as those manufactured by Microvision, Inc., are capable of creating bright, sharp images with a large depth of focus. The depth of focus, which is frequently tens of meters long, is referred to as “infinite focus” because it allows the projector to focus at such a wide range of distances that it approximates an infinite depth when compared to the area of a single pixel or image element. These scanned laser projection systems can be designed with compact form factors at a reasonable cost. These systems consume small amounts of power yet deliver vivid, complex images.
One challenge associated with these systems is size reduction. It can be desirable to make the systems smaller, so that the projection systems can be used in compact applications, such as handheld presentations. However, as the optical components become smaller, issues can arise. Distortion of images can be introduced. Similarly, optical artifacts can become a problem.
It would be advantageous to have a compact projection system that does not distort projected images.
Skilled artisans will appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the elements in the figures may be exaggerated relative to other elements to help to improve understanding of embodiments of the present invention.